Governing apparatus



GOVERNING APPARATUS Filed Sept. 12, 1923 2 Sheets-Sheet 1 O A g (0 WITNESS I RNVEN 7 1! 0 M l ,1 BY

April 14, 1925. 1,533,888

r J. MYERS GOVERNING APPARATUS Filed Sept, 12 1923 2 Sheets-Sheet 2 J. 5. Myers INVE TOR ATTORN EY WITNES I Patented Apr. 14, 1925.

rinirsn s'ra'rss PATENT oF icE,

JOE-IN S. MYERS, OF PHILADELPHIA, PENIISYLVANIA, ASSIG-NOI-t TO XVESTINGHOU$E ELECTRIC AND MANUFACTURING CGMPANY, A-GOZEPORATIOK OF PENNSYLVANIA.

' GOVERNING APPARATUS.

Application filed September 12, 1923.

To all iii/20m it may concern.

Be it known that 1, JOHN S. MiYERS, a citizen of the United States, and a resident of Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented a new and useful Improvement in (Florerning iipparatus, of which the following-3; is a specification .i 'y 'ivention relates to fluid-governing l apparatus of the character referred to in the application of Henry ll. Schmidt, Serial Xe 604,033, tiled November 29, 19:22, and

v gned to the lVestinghouse Electric and Manufacturing Company, and it has for its object shall be capable of effectively pet governing operations while employing a less quantity of motive fluid for its actuation. p

lilore particularly, my invention consists in the provision of an operating piston which has a single ttace subject to the effect of fluid pressure in order to move the opersting piston in one direction, the piston 1 'alve for the operating piston and a piston portion defined by a stem of the operating piston being depended upon to aitord sutli- -cirnt piston area to secure operation of the opci t ng piston and of its valve in the other direction. e

i rpparatus made in accordance with my invention is illustrated in the accompanying drawi forming apart of this applicain which Fig. 1 is a view, partly in tion and partly in section, showing a actor whi and i 3 is a sectional view taken along the 40 .e 111 111 oi Fig.

rrino now more particularly to the drawings for a detailed description of my invention,

show suitable apparatus, such a turbine 10, having an admission valve 11 whose position is determined by fluidc'overning apparatus, at 12,which is supplied with iluid under pressure from the impeller 13: driven by the shaft 13' of the turbine.

The governing apparatusat so 12, com- Uo provide apparatus of this chardescribed.

Serial No, 662,316.

prises a housing 1 1, which is provided with an operating cylinder 15 and with a supply chamber 16, the latter being connected, by means of a conduit 1?, to the housing 18 of the impeller 18, so that fluid under pressure, which varies as the square of the speed of the turbine shaft 14, is supplied to the supply chamber 16.

A piston member 20 is arranged within the housing 1.4: and ithas an operating piston portion 21 which is arranged within the operating cylinder 15. The piston portion 21. is provided with a piston face 22, which is, in operation, subject to the etlect of fluid under pressure in a manner to b An exhaust connection is provided for the operating cylinder 15 at the end of the latter opposite to said piston face 22. v

The piston member 20 is preferably made hollow, and, in addition to the piston portion 21, it is provided with upper and lower of the piston member 20 extends downwardly and into the supply chamber 16 and is at all times, subject to the fluid under pressure within the supply chamber 16, tending to force it upwardly. V

The operating cylinder 15 is provided with head portions 29 and 30 which cooperate with the hollow stems 24; and 25, respectively, in a fluid tight manner.

The operating piston portion 21 is provided with upper ports 31 leading from the interior of the hollow thereof to the upper face 22 and with another series otports 32 leading from the hollow thereof to the space beneath the piston portion 21; A ho low piston valve is arranged within the piston member 20 and it is provided with ports 35, which, when in registry with the ports 3., permit oi the passage of fluid un- 1 lUU the result that, upon the admission of fluid pressure thereto, the piston portion 21 is moved downwardly. The hollow piston valve member 34- is also provided with a constricted portion 36, which, when the blocking portion 37, separating the ports 35 from the constricted portion 36, is moved upwardly suiliciently to afford communication of the space above the piston portion 21 through the ports 31, the constricted portion 36, and ports with the space below the piston portion 21, allows for the exhaust of fluid above the piston portion 21 to the space below the latter and to the exhaust connection 23;

As already pointed out in the application of Henry F. Schmidt aforesaid, the hollow piston valve member 34- is closed at its upper end by a suitabl piston portion and it is connected to the piston member by means of a large spring 39 which serves to bias the piston valve 3% downwardly with respect to the piston member 20. The piston valve member 3a is also connected to the bottom of the housing" 1% by means of a small scale spring so which serves to bias the piston valve member downwardly with respect to the housing 1%. The purpose of the large sp is to afford high resistance to fluid )ressure and the puroose of the smaller or scale spring is to permit of variations in the aggregate of opposing spring pressure.

As further pointed out in said application of Henry F. Schmidt, a single spring oi adequate strength, in order to give the requisite movement for valve operation, would be inordinately 1on spring of reasonable length for the required deflection would be too weal: to secure proper operation and to withstand fluid pressures involved with apparatus of this character. Consequently, the large spring 35) is of the floating type and it carries the major. portion of the load resisiing the fluid pressure although its deflection in operation very small. The scale spring 16 affords additional resistance and the extent of its deflection is dependent upon the iiuid pressure, which, in turn, depends upon the speed.

The effect or" the load spring 39 and ot the scale spring 40 will be clearer from a statement oi. the operation of the apparatus so far described. Assuming that all parts are at rest and that the turbine 10 is being started and that there is no pressure within the supply chamber 16, the large spring 39 ras pulled the piston valve 3%- t its lowest position relative to the operating piston member 20 and the small spring L0 has pulled the piston valve and w h it the operating piston member 20 to its lowest position with respect to the cylinder 15. In this position the turbine admission valve 11 is wide open. With no pressure in the sup- On the other hand, a

brief ply chamber 16 the port is in communication with the port 41 leadingto the upper If J race 22 or the piston portion 21. Vhen the turbine is star ed fluid pressure from the impeller 18 begins to build up in the supply chamber 16 beneath the piston portion 25, tending to force it upwardly. rial) the szunc time, it builds up above the piston portion 21 against the face 2-2 tending to force it downwardly. Inasmuch as the area of the face 22 is greater than that of the stem portion 25, the fluid pressure acting against the greater area oi the race 22 holds the piston down. The piston 20 remains in this position until the fluid pressure builds up sulliciently in response to the increasing speed of the turbine, that acting against the piston portion 38 of the piston valve it overcomes the force exerted by the springs 59 and 1-0, w rich are acting to pull the piston Valve to its lo est position relative to the operating piston and moves the piston valve 34': upwardly until the cut-elf portion comes opposite the port 31 in the position shown in 2. The fluid already above the piston face 22 is now trapped within the cylinder and with the fluid pressure acting continuously against the stem portion 25, the operng piston 20 is rigidly bloc-lieu in the position shown. Jrssuming now that the pressure of fluid in the supply chamber 16 lurther increases due to a further increase in speed of the turbine 10, then the fluid pressure acts upon the piston portion 38 ot' the piston valve to further raise the latter so as to place the constriccd portion 36 in communication with the ports 31 and 32- so that the space above the operating piston portion 21 may be placed in communication with the exhaust. This movement of the piston valve 3 1- involves deflection of the springs 39 and 40 to the same extent, but, as the spring 39 is much stronger, the major portion of the increased pressure is resisted by it. 'i

As soon as the space above the operating piston 21 is placed in comimuiication with theexhaust, as just pointed out, luid, under pressure in the supply chamber 16 is then efie-rrtive upon an area, whose diameter is that of the lower stem 25, to move the piston member 20 upwardly. its this upward movement continues, the scale spring Linden goes more deflection and therefore takes some or" the load borne by the large spring 39; and this upward movement continues with the transfer oi load from the large spring to the scale spring' until the piston valve moves relatively to the piston momber 20 so to bring the portion ill "into cu off relation with respect the ports 31.

3 whereupon, t is operating piston member 20 is maintained in its acquired position until a further change in iiuid pressure takes place.

Assuming that the s ecd of the turbine drops, as is the case wien overloaded, the first effect of diminished fluid pressure in the supply chamber 16 is for the piston valve 34 to move downwardly under the influence of the springs 39 and 40. Such downward movement results, of course, in the unloading of the spring 39 to a greater extent than the spring 40. Just as soon as downward movement of the piston valve 34 commences, the ports are brought into communication with the ports 31 so that fluid under pressure is supplied from the supply chamber 16 to the operating cylinder above the operating piston portion 21 so that the latter is moved downwardly. Downward movement of the piston valve 34; and of the piston member will continue until the piston valve 3% is arrested in its motion sufficiently to bring the cut-off portions 8? in registry with the ports 31. The latter operation occurs when the decrease in pressure of fluid is balanced. by the small spring 40, the large spring 39 regaining its normal load which it has whenever the portions are in cut-off position.

From the structure described, it will be apparent that the operating piston member 20 is moved downwardly by theapplication of fluidunder pressure to the upper piston face 22, whereas upward movement of the piston member 20 is secured by the application of pressure to the lower face of the stem 25 andto the lower piston surface of the piston valve 34 and of the head portion 38, so that the total effective lower piston area has the diameter of the lower stem porlien 25. In this structure, therefore, the controlling element 20 of the governor has a single acting piston portion 21 within the operating cylinder 15, against which fluid pressure acts only on the upper face 22, the lower face being at all times connected to the exhaust.

In the Schmidt construction aforesaid, the area of the operating piston against which the fluid pressure acts to force it upward is that of the lower portion 25 plus the annular area of the lower side of the portion 21 while the area against which the fluid pressure acts to force the operating piston down ward is the annular area of the face 22 of the portion 2i, which must always be less than. the area against which the pressure acts to force the operating piston upward.

This construction requires more fluid for operating than in my modification.

it will be apparent that with my modified construction the relative areas of the piston against which the fluid acts to force it upward or to force it downward are within the control of the designer and may be modified to suit the particular requirements. In this way, 1 provide for a saving of motive fluid to the extent of that necessary to actuate the lower face of the operating piston in the aforesaid Schmidt construction. and, as a result, provide an apparatus more sensitive to the rotational velocity of the impeller. i

In order that the governing apparatus referred to may be adjusted for operation at different speeds, it is necessary that provision be made for changing the tension of the large spring 39. Accordingly, I provide a central screw member 42 engaged within the lower end of the spring 39 and having threaded connection'with respect to 'a sleeve 43, carried by the piston member 20, and having a splined connection with respect to a worriwheel or gear 44E meshing with a. worm 45. The central screw member i2 is held against rotation by a spline con ncction e2 with a ring 42", which is in turn secured to the piston portion 25. Turning of the worm 45 in one direction or the other has the effect of elevating or low ering the stem 42 in order to decrease or to increase the tension of the spring 39. Change in tension of the spring 39 results in a changein the pressure necessary to bring the piston valve 34 and the piston member 20 in such relative positions that the portions 37 occupy a cut-olf position with respect to the ports 31. In other words, change in the tension ofthe spring 39 means a change in the base load or pressure, and this, in turn, calls for a change in speed of the impeller 13 and, therefore, of the turblue 10. lVith a given adjustment of the load spring 39, any fluctuations in load are taken care of by the fluctuations in speed within the limits of the scale spring 40.

l-Vhile I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications, without departing from the spirit thereof, and I desire, therefore, that only such limitations shall be placed thereupon as are imposed by the prior art or as are specifically set forth in the appended claims. v

hat I claim is:

1. In a fluid-pressure actuated governing apparatus, the combination of a controlling element having a single-acting operating piston portion actuated in one direction by intermittent admission of fluid under pressure thereagainst and a stem portion sub jected at all times to fluid under pressure for moving the controlling element in the op posite direction, a valve for admitting and exhausting motive fluid to the operating piston portion, means for biasing the valve toward a fixed position'relative to the controlling element, and further means for biasing the valve toward a stationary element.

2. In fluid-pressure actuated apparatus, the combination of a piston having a singleacting operating portion, a valve Within the piston for admitting and exhausting motive fluid to the active face of the single-acting portion, a spring for connecting the piston and the valve, and a second spring for connecting the 'alve to a stationary part.

i 3. In hind-pressure actuated apparatus, the combination of a hollow-piston member having a piston portion and guide portions, a piston within the piston member for controlling the admission of motive fluid to one face of the piston portion to secure actuation of the piston member in one di rection, spring means connecting the piston member and the piston, one face of a guide stem of said piston member and said piston serving as a piston to secure actuation of the piston member in the other direction, and a second spring connected to the piston and to a stationery part.

l. In fluid-pressure actuated apparatus, the combination of a housing providing an operating cylinder and a fltttl-SUPP'I" chamher, a piston member having a piston portion fitting Within the operating cylinder and a stemiportion extending into the supply chamber, a piston Within the hollowpiston member for controlling the admission of motive fluid from the supply chamber to one face of the piston portion and the exhaust of fluid therefrom, spring means for connecting the piston member to the piston, and other spring means for connecting the piston to the housing.

5. In fluid-pressure actuated apparatus, the combination of a housing having an operating cylinder and a motive fluid supply chamber, an operating piston Within the cylinder and having a stem extending into the supply chamber, a valve for controlling the admission of motive fluid from the supply chamber to one face of the piston and the exhaust of fluid therefrom, a spring for connecting the valve to the piston, and a seconc spring for connecting the valve to the hous- 111g.

6. In fluid-pressure actuated apparatus, the combination of a housing having an operating cylinder and a motive-fluid supply chamber, an operating piston Within the cylinder and having a stem extending into the supply chamber, said operating cylinder having an exhaust connection at one end, a piston for controlling the admission of fluid from said chamber to one face of said operating piston and the exhaust of fluid from the latter to the other side of said piston and to the exhaust connection, a spring for connecting the operating piston to the valve, and a second spring connected to the valve and to the housing. 7

7. In fluid-pressure actuated apparatus, the combination of a part to be governed, a housing having an operating cylinder and a fluid supply chamber, a hollow operating piston member having a piston portion fitting in the operating cylinder and having upper and lower stem portions, the upper stem portion being connected to the operating element and the loWer stem portion extending into the supply chamber, a piston vithin the hollow piston member for controlling the admission and exhaust of fluid to one face of said piston portion, a spring for connecting the piston member to the valve and opposing the effectof fluid pressure applied to the latter, and a second spring connected to the valve and to the housing and also opposing the effect of fluid pressure appliedto the valve.

8. In fluid-pressure actuated apparatus, the combination of a housing having an operating cylinder and a fluid-supply chamher, a hollow-operating piston within the cylinder, a valve member Within the piston and having a piston portion, spring means for connecting the valve member to the operating piston and spring means for connecting the valve member to the housing.

9. In fluid-pressure actuated apparatus. the combination of a housing having an operating cylinder and a supply chamber, the operating cylinder having an exhaust connection at one end, an operating piston Within the operating cylinder, a valve for controlling the admission of fluid from the supply chamber to the face of said operating piston opposite to the exhaust connection and the exhaust of fluid from said face of the operating piston to the other side of the latter and to the exhaust connection, a spring for connecting the valve to the piston, and a second spring for connecting the valve to the housing.

10. In fluid-pressure actuated apparatus, the combination of a housing having; an operating cylinder and a supply chamber, the operating cylinder having an exhaust connection at one end thereof, an operating piston Within the operating cylinder and having a stem extending into the supply chamber, a piston valve Within the operating piston and the stem for controlling the admission of fluid from the supply chamberto one face of said operating piston and the exhaust of fluid from the latter to said exhaust connection, a spring for connecting the operating piston and the piston valve, and a second spring for connecting the piston valve to the housing, said piston valve having a piston portion which is effective with the piston area of the lower face of said stem to provide for movement of the operating piston and of the valve in a direction opposite to movement of the operating piston in response to fluid pressure admitted to said facej 11. In fluid-pressure actuated apparatus, the combination of a housing having an operating cylinder, a hollow piston member lit) Within the housing and having a piston portion Within the operating cylinder and a stem provided with a piston portion a piston valve for controlling the admission of fluid to one face of the operating-piston portion and having apiston portion, the latter piston portion and the piston portion of said stein being arranged oppositely to the effective face of said operating piston portion, a spring for connecting the piston member to the piston valve, and a spring for 1 ber, 1923.

JOHN s. MYERS. 

